Crankless motor-compressor



CRANKLES S MOTOR COMPRESSOR Filed April 21, 1932 2 Sheets-Sheet l Oct.17, 1933.

R. WITKIEWICZ ET AL CRANKLES S MOTOR COMPRES SOR' Filed April 21, 1932 2Sheets-Sheet 2 N Q a:

MIN

-S: HUSH Patented Oct. 17, 1933 UNITED STATES 1,930,786 CRANKLESSMOTOR-COMPRESSOR Roman Witkiewicz and Adam Wicinski, 'Lwow, PolandApplication April 21, 1932,'Serial No. 606,716, and in Poland November7, 1931 6 Claims.

The present invention relates to improvements in cranklessmotor-compressors, more particularly motor-compressors of thistypehavlng two independent pistons working in opposite directions.

The working principle of crankless motorcompressors having two pistonsindependent of one another and working in opposite directions is alreadyknown. The internal combustion device for developing power is arrangedin the space between the two pistons, whilst the com pressor mechanismis arranged in the outer chambers. Hitherto this arrangement has eitherbeen provided in the power developing device with a special ventilatingpump for the purpose of ventilating the compression chamber or hasutilized the kinetic energy of the combustion gases in the exhaust pipeand the vacuum produced thereby in the cylinder, for the suction offresh air.

The object of the present invention is to provide a cranklessmotor-compressor having two independent pistons working in oppositedirections in which the admission of fresh air into the combustion spacein an amount necessary for the combustion of the fuel is effected bymeans of a special arrangement of the control ports in the cylinderwalls, a suitably modified fourstroke combustion cycle being employed atthe same time.

The invention consists essentially in that the suction ports arearranged on the one side and the exhaust ports on the other side of thetransverse medial plane of the cylinder, that is to say, the transverseplane of symmetry of the cylinder, and are in communication with theatmosphere by means of automatic non-return valves, the stroke of theone piston being greater than the distance of the suction ports from theplane of symmetry and the stroke of the second piston being greater thanthe distance. of the exhaust ports from the said plane. As a .result ofthis arrangement a vacuum is produced in the cylinder and a suction offresh air necessary for'the combustion is made possible by means of thisvacuum..

The accompanying drawings illustrate by way of example, twoconstructional forms of the subject of the invention, and in particular:

Fig. 1 shows a longitudinal section of one construction ofthemotor-compressor according to the invention,

Fig. 2 a longitudinal section of a modified construction.

Referring first to the construction according to Fig. 1, the referencenumeral 1- denotes a cylindrical shaped frame which is cooled by meansof water, 2 and 3 are two interchangeable cylinder members in which thepistons 4 and 5 reciprocate, and 6 and 7 are two cylinder head membersin which are arranged the delivery valves 8 and 9 respectively of thecompressors. The suction valves 10 and 11- of the compressors are alsoarranged in the covers of the cylinder heads 6 and 7. By means of thesevalves the two outer sides of the two pistons function in known manneras one-sided air compressors, the return stroke of the pistons to themiddle of the cylinder being produced by the expansion of the aircontained in the comparatively large clearance spaces of thesecompressors.

The exhaust ports 12 for the combustion space between the pistons arearranged in the wall of the cylinder member 2, these exhaust ports beingin communication with an exhaust pipe 13 which is closed by an exhaustvalve 14. The suction ports 15 on the other hand are arranged in thewall of the cylinder member 3 and are in communication with theautomatic suction valve 16. The ports 12 and 15 are arrangedunsymmetrically with respect to the transverse medial axis of thecylinder which passes through the fuel valve 17 and the starting valve19.

The mode of operation of the power developing device of themotor-compressor according to- Fig. 1 is as follows:

The movement of the pistons is started in any suitable known manner, forexample by means of compressed air.

During the movement of the pistons from the position shown in the figuretowards the centre of the cylinder, a compression of the air situatedbetween the pistons begins at the instant when the piston 4 covers theexhaust ports 12. When a certain pressure is reached during thecompression an injection of fuel through the fuel valve 1'7 occurs, thisbeing efiectedcby means of a pneumatically operated pump of knownconstruction. After the injection the fuel is burnt and the pistonstravel back towards the outer ends of the cylinder. Assoon as the piston4 uncovers the exhaust ports 12 again, a partial escape of thecombustion gases occurs, the automatic valve 14 being opened thereby,but as soon as the pressure within the cylinder has fallen toatmospheric pressure this valve closes again. In the meantime thesuction ports 15 have been uncovered by the piston 5. On account of thefurther movement of the pistons a vacuum is produced in the cylinder,the suction valves 16 are opened and the air which enters the cylinderfills the space between the piston 5 and the column of combustion gaseswhich moves along behind the piston 4, the length of this column beingequal tothe distance between the piston 4 and the suction ports 15 atthe moment when the suction valves 16 open. When the pistons; haveattained their extreme outer positions the right side of the cylinder isfilled almost entirely of the excess pressure arising between the twopistons, the automatic exhaust valve 14 is opened which results in thecolumn of combustion gases between the left hand piston 4 and the columnof fresh air, which may be regarded as a continuation of the righthandpiston 5, being entirely or for the most part expelled. As soon asthe piston 4 covers the ports 12 again, the compression of the fresh airand also any combustion gases which may have remained, begins and thecycle of operation which has been described commence anew.

From the above description it will be seen that the motor-compressoraccording to the invention does not possess any air pump for itscombustion chamber and that the mode of operation does not depend on theproduction within the cylinder of a vacuum by means of the kineticenergy of the exhaust gases, but that the suitable arrangement of thesuction and exhaust ports in the combustion space is employed forfilling the cylinder with fresh air, the individual phases of operationof a usual four-stroke cycle occurring in a modified sequence, namely,the suction after the expansion and the compression aiter the exhaust,each two strokes being in tandem arrangement.

Since the combustion in 8. Diesel cycle generally occurs in an excess ofair it is not in any way necessary to remove all the combustion gasesfrom the cylinder. On the contrary it is advantageous to leave a portionof the combustion gases in the cylinder since the end temperature of thecompression is thereby increased and the combustion is thus facilitated.A partial retention of the combustion gases in the. cylinder may bebrought about intentionally by the provision of a pipe 18 by-passing theexhaust'valve 14. During the suction period the combustion gases returnto the cylinder through this pipe and the quantity of air sucked in isthus reduced.

Figure 2 illustrates a modified construction of the cranklessmotor-compressor according to the invention, which employs the sameprinciple for the suction of the air necessary for the combus tion ofthe fuel, but wherein the suction valves of the compressors are notprovided in the (ylinder heads but are arranged considerably m arer'thecentre of the cylinder and serve at the same time for the completion ofthe working phases of the power developing device.

This modified construction again consists essentially in a cylindricalshaped, water cooled frame 20, two cylinder members 21 and 22 in whichthe pistons 23 and 24 reciprocate and two cylinder head members 25 and26 in which only the delivery valves 2'1 and 28 respectively of thecompressors are arranged: The exhaust ports 29 for the combustionchamber and also the suction ports 30 are arranged at suitable places inthe cylinder member 21. The cylinder member 22 on the other hand isprovided only with the suction ports 31. The automatic suction valves 32and 33 are arranged in such a manner that the suction ports 30 and 31communicate with one another by means of a pipe 34 which permits of anequalization of any differences in the throttling of the air which mayoccur in the valves 32 and 33; -The exhaust ports 29'communicate withthe exhaust pipe 35 at the outer end of which is arranged the automaticexhaust valve 36.

The compressors are arranged on the outsides of the two pistons andoperate in known manher with the aid of the suction ports 30 or 31 andthe delivery valves 27 or 28 respectively, the return stroke of thepistons being effected in a manner analogous to that already describedwith reference to the construction shown in Figure 1.

During the movement of the pistons from the position shown in Figure 2towards the centre of the cylinder, the compression of the air in thecombustion space begins at the instant when the exhaust ports 29 arecovered by the piston 23. As soon as the pressure has reached a certainvalue the injection of fuel from the fuel valve 49 results in the manneralready described. During its return stroke the left piston 23 nowuncovers the exhaust ports 29 so that a partial escape of the combustiongases occurs, the automatic exhaust valve 36 being opened thereby. Theinner edges of the suction ports 30 and 31 are so arranged that thepistons 23 and 24 respectively uncover them when the pressure .betweenthe pistons has fallen to atmospheric pressure, and at this instant, theautomatic exhaust valve 36 closes. On account of the further movement ofthe pistons towards the ends of the cylinder, a vacuum is producedbetween the pistons which results in the suction of fresh air throughthe suction valves 32 and 33, the air which enters the cylinder fillingup on the one hand the space between the suction ports 30 and the piston32, and on the other hand the space between the ports 31 and the piston24. During the reverse movement of the two pistons towards the centre ofthe cylinder there is expelled from the space between them the column offresh air which is situated between the suction ports 30 and the piston23 and also partly or completely the column of combustion gases which issituated between the ports 30 and 31. ously the column of fresh airwhich was between the ports 31 and the piston 24 fills up the spacebetween the ports 31 and 29, and is compressed together with any of thecombustion gases which may remain behind.

The content of combustion gasesiin thecompressed air may be increased inthe manner already described, namely, by the provision ot a by-pass pipe3'7 for the exhaust valve 36. By building one or more exhaust valvesinto the exhaust pipe 35, which is of a certain length, the movement ofthese valves may be diminished whereby rapid wearing of the valves isprevented.

The constructional form of the motor-compressor just described ischaracterized in that the suction ports which serve for the suction offresh air into the combustion space, are also employed for the suctionof the fresh air into the compressor chambers. This constructional formis more advantageous than that according to Figure 1, in that a coolingof the exhaust.-

valve is effected by the constant expulsion of a part of the suction airthrough the exhaust pipe.

The starting of the motor-compressor is effected by means of compressedair through the medium of a starting valve 19 (Fig. 1) or 38 .(Fig. 2).f

The motor-compressor described above is provided with no regulatingapparatus since it operates with the so-called automatic regula-Simultanetion, which consists in that an increase in the 7 end of theoutward strokes quantity of compressed air automatically follows anyincrease in' the quantity of injected fuel. This may be explained in thefollowing manner 9 If the quantity of injected fuel is only justsuflicient, for example, for running light, the pressure of compressionon the compressor sides of the pistons attains the value of the workingpressure and the movement of the pistons is reversed at this instantwithout any air having been expelled generally speaking. Any increase inthe quantity of injected fuel results in an increase in the kineticenergy of the pistons and the motion of these is reversed only after acertain quantity of air has quantity is the greater the more the amountof fuel injected.

We claim:

1. In a crankless motor-compressor of the type having two pistons freelyworking in opposite directions in a common cylinder, the internalcombustion engine being arranged between two pistons, the combinationof: a working cylinder; two pistons adapted to work within the saidcylinder freely in opposite directions; a suction port arranged on oneside of the transverse plane of symmetry of the cylinder; acommunicating conduit between said suction port and the outeratmosphere; an automatic nonreturn valve controlling said conduit; saidsuction port being adapted to be controlled by the adjacent piston, thestroke of said adjacent piston being greater than the distance of saidport from said plane of symmetry, whereby a vacuum is produced in thecylinder at the end of the out stroke and suction of fresh air forcombustion occurs at the end of the out stroke; and an exhaust port onthe other side of the transverse plane of symmetry of the cylinder, saidexhaust port being adapted to be controlled by the second piston, thedistance of said exhaust port from the plane of symmetry being less thanthe stroke of the second piston,- substantially as described.

2. In a crankless motor-compressor of the type having two pistonsworking freely in opposite directions in a common working cylinder, thecombination of: a working cylinder; a first working piston; a secondworking piston; said two working pistons being adapted to work freely inopposite directions in said cylinder; an exhaust port on one side of thetransverse plane-of s metry of the cylinder; a communicating conduitbetween said exhaust port and the outer atmosphere; automatic non-returnvalve means for controlling the flow of the gas through said conduit;suction ports arranged on both sides of the transverse plane of symmetryof the cylinder; communicating conduits between said suction ports andthe outer atmosphere; valve means for controlling said communicatingconduits; said suction ports being arranged at a lesser distance fromthe transverse plane of.

symmetry of the cylinder than the outward strokes of the pistons,whereby at the end of the out strokes of the two pisto a vacuum isproduced and fresh air suction occurs at the at both ends of thecylinder, substantially as described,

3. In a crankless motor-compressor of the type having two pistonsworking freely in opposite been expelled, which,

automatic pistons at the end directions in a common cylinder, thecombination of: a working cylinder; two working pistons freely workingin said cylinder in opposite directions; a suction port in said cylinderadapted to be controlled by one of the working pistons, the stroke ofsaid working pistons being greater than the distance of said suctionport from the transverse middle plane of the cylinder; a communicatingconduit between'said suction port and the outer atmosphere; and twonon-return valves controlling said communicatingconduit, substantiallyas described.

4. In a crankless motor-compressor of the type having two pistonsworking freely in opposite directions-in a common cylinder, thecombination of: a cylinder; a flrstworking piston; a second workingpiston; a suction port on one side of the transverse plane of symmetryof the cylinder adapted to be controlled by the first piston; a suctionport arranged on the other side of the transverse plane of symmetry ofthe cylinder adapted to be controlled by the second piston;communicating conduits between said suctionports and the outeratmosphere; said communication conduits being connected together by acommunicating conduit; and automatic valve means controlling said lastnamed communicating conduit, substantially as described.

5. In a crankless motor-compressor having two pistons freely working inopposite directions in a common cylinder, thecombination of: a commoncylinder; two power pistons adapted to act in opposite directions insaid cylinder; an exhaust port in said cylinder adapted to, becontrolled by one of thesaid pistons; a communicating conduit betweensaid" exhaust portand the outer atmosphere;. an automatic nonreturnvalve controlling said conduit; and a bypass to said automatic valvemeans, said bypass being so arranged as to allow of a backflow of gaspassing through the valve into the communicating conduit and backintothe cylinder, substantially as described.

6. In a crankless two pistons working freely in opposite directions in acommon wor cylinder, the space between the pistons acting as an internalcombustion engine, and the spaces between the'piscompressors, thecombination of a common cylinder; two pistons working'freely insaidcylinder' in opposite directions; at the ends of the means forcontrolling said ports; fresh air suction ports arranged on both sidesof the transverse middle plane of the cylinder; communicating conduitsbetween said ports and the outer atmosphere; valve means for controllingsaid conduits; said suction ports being so located with regard to theircorresponding controlling pistons that they are uncovered by saidpistons at the end of the inward strokes and thus serve for admission ofair-into the compressors,

motor-compressor having tons and the ends of the cylinder acting as air5 cylinder; automatic valve and are also uncovered bytheir correspondingof the out strokes and thus serve for the admission of fresh air intothe internal combustion engine at the end of the out strokes,substantially\as described.

ROMAN wrr'xmwroz.

